Problem: If $4a + 3b + c = 1$ and $5x + 3y = 7$, what is $-35x + 24b - 21y + 32a + 8c$ ?
Solution: $= 32a + 24b + 8c - 35x - 21y$ $= (8) \cdot (4a + 3b + c) + (-7) \cdot (5x + 3y)$ $= (8) \cdot (1) + (-7) \cdot (7)$ $= 8 - 49$ $= -41$